/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.runtime.checkpoint;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.Serializable;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Delegate class responsible for checkpoints cleaning and counting the number of checkpoints yet
 * to clean.
 */
public class CheckpointsCleaner implements Serializable {
	private static final Logger LOG = LoggerFactory.getLogger(CheckpointsCleaner.class);

	private final AtomicInteger numberOfCheckpointsToClean;

	public CheckpointsCleaner() {
		this.numberOfCheckpointsToClean = new AtomicInteger(0);
	}

	int getNumberOfCheckpointsToClean() {
		return numberOfCheckpointsToClean.get();
	}

	public void cleanCheckpoint(Checkpoint checkpoint, boolean shouldDiscard, Runnable postCleanAction, Executor executor) {
		numberOfCheckpointsToClean.incrementAndGet();
		executor.execute(() -> {
			try {
				if (shouldDiscard) {
					try {
						checkpoint.discard();
					} catch (Exception e) {
						LOG.warn("Could not discard completed checkpoint {}.", checkpoint.getCheckpointID(), e);
					}
				}
			} finally {
				numberOfCheckpointsToClean.decrementAndGet();
				postCleanAction.run();
			}
		});
	}
}
